# Species-Specific Color Preferences During Foraging in Aedes aegypti, Aedes albopictus, and Culex quinquefasciatus Across Varying Light Conditions

## TL;DR

This study shows that different mosquito species and sexes prefer different colors when foraging, depending on the light conditions, which could help improve mosquito traps.

## Contribution

The study reveals species- and sex-specific color preferences in mosquitoes under varying light conditions, offering insights for targeted vector control.

## Key findings

- Aedes mosquitoes prefer red in dim light and black in bright light, with sex-specific differences.
- Culex mosquitoes show strong attraction to black in dim light, with females shifting to red in bright light.
- Color preferences are influenced by light intensity, species, and sex, impacting trap design for vector control.

## Abstract

Mosquitoes are responsible for spreading many serious diseases, making it important to understand their behavior. In this study, we looked at how three mosquito species (yellow fever mosquito, Asian tiger mosquito, and southern house mosquito) respond to different colors while searching for food. Using a simple method of coloring food with ink, we observed how the mosquitoes reacted to food under different light conditions, like daytime and low light. In darkness, mosquitoes showed no clear color preference, relying only on smell. In dim light, the Aedes species started to prefer lighter colors, especially red, likely because it stood out more. This was most noticeable in Asian tiger mosquito males and females. In bright light, these mosquitoes switched to preferring black, possibly because of stronger contrast or camouflage. The Culex species behaved differently: both sexes preferred black at dusk-like light, but females switched to red in bright light, while males kept preferring black. These findings show that mosquitoes react differently to color depending on the light level, their species and sex. Knowing this can help improve traps and control strategies tailored to each mosquito type.

Mosquitoes are key vectors of numerous infectious diseases, making the study of their behavior essential for effective control strategies. This study investigates the color preferences of Aedes aegypti, Aedes albopictus, and Culex quinquefasciatus during foraging, using an ink-based staining method to assess feeding behavior under varying light intensities (0, 130 and 1600 lx). At 0 lx, no consistent visual preferences emerged, confirming reliance on olfactory cues only. Under dusk-like illumination (130 lx), diurnal Aedes exhibited a tendency to approach red stimuli (probably perceived as grey) over darker targets, with Ae. albopictus females and males showing significant preference for red over green responses, indicating early salience of red contrasts. At high illumination (1600 lx), Aedes shifted preference toward black, especially in males, reflecting dominance of achromatic contrast and camouflage considerations. In contrast, crepuscular Cx. quinquefasciatus showed strong attraction to black at dusk-like light in both sexes; at high illumination, females’ preferences shifted from black to red, whereas males maintained or reverted to black preference across assays. These divergent patterns align with differences in photoreceptor sensitivity, contrast processing, and ecological niches governing host- and swarm-seeking. Identifying how dusk-like versus bright light modulates color-driven behavior provides insights for designing trap colors and illumination regimes optimized for specific mosquito species and sexes, thereby enhancing targeted vector-control strategies.